An antimicrobial peptide of the cathelicidin family that provides innate immune defense by killing pathogens and modulating inflammation and wound healing.
This paper reviews how certain immune‑boosting proteins (LL‑37, hepcidin and β‑defensin‑2) are naturally made by stem cells and can kill bacteria by messing with their cell membranes. It explains the basic ways these peptides work and why scientists think they could become new infection‑fighting drugs, but it doesn’t give any real‑world dosing or treatment tips.
Zaura. Egija E; Brandt. Bernd W BW; Buijs. Mark J MJ; Emingil. Gülnur G; Ergüz. Merve M; K...
In kids and teens with a rare immune disorder called severe congenital neutropenia, the natural antimicrobial peptide LL‑37 in saliva is about the same as in healthy people, but they still have a lot of gum bleeding, inflammation, and an unhealthy mouth bacteria mix.
The study shows that the human antimicrobial peptide LL‑37 makes harmless skin bacteria (commensal Staphylococcus epidermidis) turn on a defense system more strongly than it does in disease‑linked strains, but this doesn’t change the bacteria’s membrane composition.
Kraaij. Marina D MD; van Dijk. Albert A; Scheenstra. Maaike R MR; van Harten. Roel M RM; Haagsman. H...
The study shows that a chicken peptide called CATH-2 can make chicken immune cells show more markers that help present antigens, while the human peptide LL‑37 did not have this effect in the same cells. It also found that CATH-2 can lower a specific inflammation signal in chicken cells. These results are limited to chickens and don’t tell us what would happen in humans.
The study measured several immune‑activating proteins (including the antimicrobial peptide LL‑37) in the sputum of people with asthma, COPD, and the mixed condition asthma‑COPD overlap (ACO). It found that LL‑37 levels are higher in ACO than in asthma but lower than in COPD, and that LL‑37 can help tell asthma from COPD in a lab test. The work is mainly about using LL‑37 as a diagnostic marker, not about taking it as a supplement or therapy.
The study shows that MRSA bacteria with the cfr gene are tougher against the body’s natural peptide LL‑37 and antibiotics, making infections harder to treat. Using the antibiotic linezolid together with rifampicin works much better than linezolid alone, cutting the needed dose and improving outcomes in mouse infection models. This finding is mainly relevant for clinical treatment, not for DIY health hacks.
In kids with community‑acquired pneumonia, blood levels of the immune trap NET, the peptide LL‑37, and free DNA go up, while the enzyme DNase I goes down. These changes track how severe the infection is, but the study only shows they could help doctors diagnose and gauge pneumonia, not that taking LL‑37 will boost health.
Yu. Yangsheng Y; Cooper. Christopher L CL; Wang. Guangshun G; Morwitzer. M Jane MJ; Kota. Krishna K;...
Scientists found that the natural peptide LL-37 and specially engineered versions can stop Ebola virus from infecting cells in lab experiments. The engineered peptides work better because they resist being broken down inside cells.
Kopfnagel. Verena V; Dreyer. Sylvia S; Baumert. Kathrin K; Stark. Maximilian M; Harder. Jürgen...
The study shows that the skin peptide RNase 7, not LL‑37, can turn our own DNA into a warning signal that makes skin cells produce antiviral chemicals and fight herpes virus. LL‑37 did not have this effect in the experiments.
The study shows that the natural peptide LL‑37 can trigger strong inflammation and changes in joint‑cell behavior, especially when paired with another inflammatory molecule, IL‑17A. This could make arthritis worse, but it doesn’t give any direct tips for health hacks or longevity.
Pan. Wen Liang WL; Wang. Yan Y; Hao. Yuan Y; Wong. Jack Ho JH; Chan. Wing Cheong WC; Wan. David Chi-...
The study found that the antimicrobial peptide LL‑37 works together with the CXCR4 receptor to help breast cancer cells spread, showing that higher levels of both are linked to tumors that have moved to lymph nodes. This means LL‑37 can act like a unique activator of CXCR4, making cancer cells more mobile.
de Bruyn. Magali M; Ringold. Randy R; Martens. Erik E; Ferrante. Marc M; Van Assche. Gert G; Opdenak...
Researchers created a blood test called the Ulcerative Colitis Response Index (UCRI) that includes the peptide LL‑37 along with other markers to tell if ulcerative colitis patients are healing after anti‑TNF therapy. The test works fairly well, but it’s only useful for people with active ulcerative colitis, not for healthy individuals looking to boost longevity or performance.
Researchers found that people with psoriasis, especially those who develop psoriatic arthritis, have higher levels of immune proteins (autoantibodies) that target a peptide called LL-37. These antibodies rise with disease severity and might help track or treat the condition, but the study does not give any direct ways to use this information for health optimization.
Scientists put a small protein called LL-37 onto specially textured titanium surfaces that are used for bone implants. In lab tests and in rats, this coating helped stem cells that can become bone cells move to the implant, stick to it, and turn into bone, leading to faster and stronger new bone growth around the implant.
Researchers created a score that predicts which lupus patients are likely to get infections in the next year. The score uses immune cell counts, a gene marker (TLR2), and whether the patient is on cyclophosphamide. They also found that patients who got infections had more of a protein called LL-37 in their immune traps (NETs).
Caiaffa. Karina S KS; Basso. Fernanda G FG; Santos-Filho. Norival A NA; de Souza-Costa. Carlos Alber...
The study tested LL‑37 and similar peptides on dental‑like cells and found that LL‑37, at a certain concentration, boosted markers of mineral formation without killing the cells, but it didn’t change key genes linked to dentin growth. The other peptides were less effective or toxic at higher doses.
Malhotra. Sankalp S; Hayes. Don D; Wozniak. Daniel J DJ
This paper reviews how cystic fibrosis (CF) lungs get damaged by a stubborn bug called Pseudomonas aeruginosa and how the body’s own defenses, especially a natural antibiotic called LL‑37, try to fight it. It explains that the disease gets worse because the immune system overreacts and the bacteria develop tricks to avoid being killed, but it doesn’t give new treatment steps for everyday use.
Huang. Yueyang Y; Alumasa. John N JN; Callaghan. Lauren T LT; Baugh. R Samuel RS; Rae. Christopher D...
A lab study found that a new compound called KKL-40 can stop the growth of Staphylococcus aureus, including drug‑resistant strains, and works even better when combined with the natural human peptide LL‑37. The combo kills the bacteria without harming human cells and bacteria hardly become resistant, but the drug isn’t available for personal use yet.
The study shows that a natural mix of harmless mouth bacteria can make gum tissue thicker and more protective, boosting some antimicrobial proteins but not the peptide LL‑37. This suggests a healthy oral microbiome helps gum health, but it doesn’t give any new tricks for using LL‑37 itself.
Gontsarik. Mark M; Yaghmur. Anan A; Ren. Qun Q; Maniura-Weber. Katharina K; Salentinig. Stefan S
Scientists made a tiny carrier that bundles the natural antimicrobial peptide LL‑37 with oleic acid. This carrier changes shape when the environment gets more acidic, turning the peptide's bacteria‑killing power on, and stays inactive at neutral pH. The work shows a way to target antimicrobial action to specific body sites, but it doesn’t give a ready‑to‑use method for everyday health hacking.